Chill a cocktail glass with very cold ice water while preparing your drink.
Add ice and all ingredients to your shaker and shake for 10-12 seconds.
Discard ice water and strain cocktail into the chilled glass. Cheers!
Notes
I used a rum mix of a French white rum, a Jamaican dark rum and a Nicaraguan dry Rum. You can just use your favorite rum or try mixing a few that you love. The bartenders I spoke to use a rum mix.
Make sure you shake longer than you think you should. This cocktail is only good if you have a really cold cocktail!